Iran on Friday blamed "interfering countries" for making Kofi Annan's mission fail in Syria, and implied it could now be among those taking "a more crucial role" in solving the conflict.

"It seems that interfering countries were not satisfied with the efforts made by Annan to halt the shipment of arms into Syria and (to put an end) to terrorist acts," foreign ministry spokesman Ramin Mehmanparast said during a visit to China, according to Iran's official IRNA news agency.

"Not only did they not put in any effort to implement Annan's six-step plan... these countries endeavoured to have his mission fail," he charged.

He did not name any countries, but Tehran in the past has accused Saudi Arabia, Qatar and Turkey of arming Syria's rebels in collusion with the United States and Israel.

Mehmanparast said that following Annan's resignation on Thursday as international peace envoy for Syria, "independent countries in the region will now have a more crucial role" in resolving the crisis.

The choice of words implied he was talking about Iran, which is Syria's key ally in the region and which has provided Damascus with humanitarian, economic and political support.

Those countries, Mehmanparast was quoted as saying, "should prepare the ground for dialogue between the (Syrian) government and the rebels."